In process control technology, which preferably is applied for monitoring processes in the chemical industry or in flowing or standing bodies of water, sensors are arranged in a measuring environment. These sensors measure the properties of a medium to be examined and are connected with a locally removed, process control center. In order to be able to operate such a sensor, there is arranged on a sensor unit comprising the sensor an explosion resistant housing, which contains electrical components. Included among the electrical components is a measurement amplifier, which drives the sensor and evaluates the signals output by the sensor. This measurement amplifier is connected with the sensor unit via a number of interfaces.
For mechanical connection, the explosion resistant housing includes a holder, which bears a circuit board, on which the measurement amplifier is secured. The electrical connection goes from the cable connected sensor to a feedthrough for the conductors of the cable. The feedthrough is introduced into the housing of the sensor unit. In such case, the conductors of the cable coming from the sensor are soldered on one side of the feedthrough with leads of the feedthrough, while on the other side of the feedthrough likewise conductors of a cable are soldered to leads of the feedthrough, and this cable goes to the measurement amplifier. The conductors of the cable leading to the measurement amplifier are soldered to an additional, explosion resistant feedthrough, which closes the explosion resistant housing off. On the other side of the explosion resistant feedthrough, cable is led directly to the measurement amplifier and then connected with the measurement amplifier by means of a plug. Such an electrical connection is not only constructively very complex and, thus, very costly, but, also, means a significant manufacturing effort.